1. Field of the Invention
This invention relates to a sun screen device that is operable so as to cover and uncover a sunroof of an automobile.
2. Description of the Related Art
FIG. 1 illustrates a conventional sun screen device that includes a pair of elongate first and second slide rails 12, a shaft unit 11, a screen unit, and a guide unit.
The sun screen device is adapted to be mounted beneath a sunroof (not shown) of an automobile (not shown), and is operable so as to cover and uncover the latter.
Each of the first and second slide rails 12 extends in a first direction, has first and second end portions 121, 122 that are opposite to each other in the first direction, and defines a rail groove 120 therein (see FIG. 2). The first and second slide rails 12 are spaced apart from each other in a second direction transverse to the first direction.
The shaft unit 11 is disposed proximate to the second end portions 122 of the first and second slide rails 12, and includes a pair of seat members 112, a shaft member 111, and a shaft cover 113. The seat members 112 are spaced apart from each other in the second direction. The shaft member 111 extends in the second direction, and has opposite end portions, each of which is coupled rotatably to a respective one of the seat members 112. The shaft cover 113 partially covers the shaft member 111.
The screen unit includes a flexible screen body 13 and an operating member 15. The screen body 13 has a securing end 131 that is secured to the shaft member 111 of the shaft unit 11, an operating end 132 that is opposite to the securing end 131 in the first direction and that is movable in the first direction, and first and second lateral ends 133 that are opposite to each other in the second direction. The operating member 15 is coupled to the operating end 132 of the screen body 13, and is operable so as to move the operating end 132 of the screen body 13 in the first direction.
The guide unit includes a plurality of ball-shaped sliding members 14. Some of the sliding members 14 are provided along the first lateral end 133 of the screen body 13 and are disposed in the rail groove 120 in the first slide rail 12. The remainder of the sliding members 14 are provided along the second lateral end 133 of the screen body 13 and are disposed in the rail groove 120 in the second slide rail 12.
In operation, when an external force is applied to the operating member 15 such that the operating end 132 of the screen body 13 moves away from the shaft unit 11, the shaft member 111 rotates in a first angular direction. This results in unwinding of the screen body 13 from the shaft member 111 and sliding movement of the sliding members 14 along the first and second slide rails 12, thereby covering the sunroof. On the other hand, when an external force is applied to the operating member 15 such that the operating end 132 of the screen body 13 moves toward the shaft unit 11, the shaft member 111 rotates in a second angular direction opposite to the first angular direction. This results in winding of the screen body 13 on the shaft member 111 and sliding movement of the sliding members 14 along the first and second slide rails 12, thereby uncovering the sunroof.
Although the conventional sun screen device achieves its intended purpose, when the screen body 13 is wound on the shaft member 111, the sliding members 14 overlap each other, resulting in bulging at both end portions of the shaft member 111. As such, a relatively large shaft cover 113 is required in order to conceal the shaft member 111.